If you're going bigger on the front make sure there's enough clearance for some chain "lash" as the chain gets pulled onto the bigger sprocket, your gearing will also change when you get the hang of corners/sections which have a long full throttle run afterwards - Union Mills, Ballagarey, Sarahs/Lambfell, Rhencullen, Quarry, Guthries etc also better to be revving out than not pulling top gear.